The book begins with an intro and materials chapter including pens, paper, and general techniques (circa 15% of the content count). The author does include a short resources list with e-tailers who carry the brush pens and types of paper which are best to use with these projects. After the intro, the lion's share of the book is given over to specific tutorials grouped by subject (animals, foods, plants, Asian art, black and white illustrations etc).
There are a number of really interesting lessons in this book concerning the use of space and movement.
One of the things that many artists struggle with is the use of negative space. Ito's simple step by step tutorials brilliantly utilize negative space to illustrate 3D shapes and volume (see the sheep example below)
Well worth a look.
Disclosure: I received an ARC at no cost from the author/publisher for review purposes.